Yes, we have to make a distinction between the genetic affect of being a part of the Roman Empire and genetic influence of having been settled by people specifically from Latium. By the time of Claudius, what percentage of the Empire's population would have been of primarily Latin Ancestry? Of course there were Latin Colonae all over the empire but I doubt they made as significant of an impact genetically as they did culturally.I didn't say Roman, I said mixed European. Within roman controlled borders peoples were mixed through auxiliary soldiery, forced en mass migrations, voluntary familial migrations, slavery. The gene pool expanded in Britain, not in the Celtic countries. I would laugh at the idea of the population of any city having any serious impact on an entire nation.
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